1. Field of the Invention
The present invention relates generally to the field of machines used for forming products, such as extruded or drawn products, wherein the product size requires uniformity. More particularly, the invention relates to a product forming apparatus having computer-based device for non-contact gauging of a product size.
2. Related Art
Presently, there exist techniques for measuring the size of a product during its formation without contacting the surface thereof. Such techniques are used in wire drawing, cable insulating, fiber production, metal tube and bar forming, centerless grinding, paper tube, hose and tube extrusion and continuous vulcanization. Some techniques employ a device which produces an analog signal which ideally exhibits a square wave form, wherein the drop in the wave indicates the portion of the signal representing the product size.
A problem which exists with such devices resides in signal interference due to harsh environments, such as, particles of dust, dirt, oil, scale, swarf, lubricant, condensate, film or moisture or temperature between the signal source and the signal receiver in addition to the product causing so much noise in the signal to render it unusable for the purpose intended. In view of this, the current devices require intermittent cleaning and/or maintenance and still remain relatively inaccurate in their ability to form a consistently sized product. Accordingly, the product consistency is poor which and leads to unwanted waste.
There is therefore a need to overcome the problems which exist with current continuous product forming devices. There is also a need to provide a device which can relatively accurately measure product size in a harsh environment.